JP7174242B2 - Semiconductor device manufacturing method - Google Patents

Description

The present disclosure relates to a method of manufacturing a semiconductor device.

Patent Document 1 discloses an optical module in which a substrate on which a photoelectric conversion element (for example, a semiconductor laser or a photodiode) is mounted and a package are hermetically sealed by solder bonding in an inert atmosphere.

Japanese Patent Application Laid-Open No. 2007-324303

However, although Patent Document 1 describes bonding a package and a substrate, when bonding is performed in a replaced atmosphere without vacuuming, moisture, gas, etc. remain on the surface of the package or substrate. . On the other hand, if vacuuming is performed, bonding is performed in a vacuum chamber, so it is considered difficult to bond both with high positional accuracy.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method of manufacturing a semiconductor device, which can join a translucent member and a package with high positional accuracy.

In order to solve the above problems, a semiconductor device manufacturing method according to an embodiment of the present invention seals a semiconductor laser element provided in a recess of a package by covering the recess with a translucent member. A method of manufacturing a semiconductor device comprising
a solder ball forming step of forming a plurality of spaced apart solder balls on the surface of the package around the recess in which the semiconductor laser element is provided, or on the surface of the translucent member facing the surface;
a temporarily fixing step of temporarily fixing the surface of the translucent member or the surface of the package by contacting the upper surfaces of the softened solder balls so that an airway leading to the recess is formed between the solder balls; ,
The interior of the concave portion is decompressed through the airway, and in a state in which the sealing gas is injected after decompressing, the translucent member and the package are heated and pressed to melt the solder ball and melt the translucent member. and a joining step of joining the optical member and the package.

According to the method of manufacturing a semiconductor device according to one embodiment of the present invention, it is possible to provide a semiconductor device capable of joining the translucent member and the package with high positional accuracy.

FIG. 3 is a perspective view schematically showing a die bonding step in the method of manufacturing a semiconductor device according to Embodiment 1 of the present invention; 3 is a perspective view schematically showing a wire bonding step in the method of manufacturing the semiconductor device of Embodiment 1; FIG. 4 is a perspective view schematically showing a solder ball forming step in the manufacturing method of the semiconductor device of Embodiment 1; FIG. 4 is a perspective view schematically showing a temporary fixing step in the method of manufacturing the semiconductor device of Embodiment 1. FIG. 4 is a perspective view schematically showing a bonding step in the manufacturing method of the semiconductor device of Embodiment 1. FIG. 4 is a perspective view schematically showing a singulation step in the method for manufacturing a semiconductor device of Embodiment 1. FIG. 2 is a perspective view showing a light-emitting device separated into pieces in the method for manufacturing a semiconductor device according to Embodiment 1. FIG. 2 is a perspective view schematically showing a wiring board mounting step in the manufacturing method of the semiconductor device of Embodiment 1. FIG. 4 is a perspective view schematically showing a collimating lens mounting step in the method of manufacturing the semiconductor device of Embodiment 1. FIG. FIG. 10 is a top view of the package of the semiconductor device of Embodiment 2; FIG. 10 is a top view of a translucent member and a wavelength converting member of Embodiment 2; 2 is a top view of a semiconductor device according to Embodiment 2. FIG. FIG. 10 is a cross-sectional view schematically showing a bonding step in the method for manufacturing a semiconductor device according to Embodiment 2; FIG. 10 is a cross-sectional view schematically showing a bonding step in the method for manufacturing a semiconductor device according to Embodiment 2;

A method for manufacturing a semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings. A method of manufacturing a semiconductor device according to an embodiment is a method of manufacturing a semiconductor device including hermetically sealing a semiconductor laser element provided in a recess of a package by covering the recess with a translucent member.

<Embodiment 1>
The method for manufacturing the semiconductor device of Embodiment 1 will be described in detail below.
In the following description, an example of manufacturing a semiconductor device including three semiconductor laser elements 1, 2 and 3 will be described. However, the manufacturing method of Embodiment 1 is not limited to the one using the three semiconductor laser elements 1, 2, and 3, and may include at least one semiconductor laser element.

In the manufacturing method of the semiconductor device of Embodiment 1, first, the package 10, the semiconductor laser elements 1, 2 and 3, and the translucent member 20 are prepared.
(1) Preparation of Packages 10 Here, an aggregate substrate 100 on which a plurality of packages 10 are provided in an aggregate state is prepared. As shown in FIG. 1, the aggregate substrate 100 includes recesses 10r in regions corresponding to the respective packages 10 (hereinafter simply referred to as packages even in the aggregated state). Positive and negative wiring electrodes to which the electrodes of the semiconductor laser element are connected are provided inside the recess 10r. Connected to the terminal electrode. Furthermore, in each package 10, a bonding metal film 10m is provided around the recess 10r. Here, the collective substrate 100 is preferably made of ceramics having high thermal conductivity, for example, in order to efficiently dissipate heat generated by the semiconductor laser elements. Ceramics include, for example, aluminum oxide, aluminum nitride, silicon nitride, or silicon carbide. Metals such as Cu, W, and Au can be used for the wiring electrodes and the external terminal electrodes. Au or the like can be used for the bonding metal film 10m. In addition, the collective substrate 100 is provided in advance with notches for singulation.

(2) Preparation of semiconductor laser elements 1, 2 and 3 As semiconductor laser elements, for example, three types of semiconductor laser elements 1, 2 and 3 of RGB (red, green and blue) are prepared. The semiconductor laser element 1 is, for example, a red light emitting laser diode (LD) element having an emission peak wavelength in the range of 605 nm to 750 nm. Examples of LD elements emitting red light include those containing InAlGaP-based or GaAs-based semiconductors. It is preferable to use an LD element that emits red light that has two or more waveguide regions. As a result, the heat generated by the laser oscillation can be dispersed over the plurality of waveguide regions, so that the output reduction due to the heat generation can be suppressed.

The semiconductor laser element 2 is, for example, an LD element emitting green light having an emission peak wavelength in the range of 495 nm to 570 nm. A GaN-based semiconductor such as one containing at least one of GaN, InGaN, and AlGaN can be used as the green light-emitting LD element.

The semiconductor laser element 3 is, for example, an LD element that emits blue light with an emission peak wavelength in the range of 420 nm to 494 nm. A GaN-based semiconductor such as one containing at least one of GaN, InGaN, and AlGaN can be used as the blue-emitting LD element.

(3) Mounting of semiconductor laser elements 1, 2 and 3 on submounts 4a and 4b Here, the semiconductor laser elements 1, 2 and 3 prepared above are mounted on submounts 4a and 4b. Specifically, the semiconductor laser element 1, which is a GaAs-based laser diode, is mounted alone on the submount 4a, for example. The semiconductor laser element 2 and the semiconductor laser element 3, which are GaN-based laser diodes, are mounted on the submount 4b together with a protective element 8 such as a Zener diode. By connecting the semiconductor laser element 2 and the semiconductor laser element 3 in parallel with the protection element 8, it is possible to prevent a voltage exceeding a certain level from being applied to the semiconductor laser elements 2 and 3. FIG.
In this way, it is optional whether or not the semiconductor laser elements 1, 2, 3 are mounted on the bottom surface of the recess 10r via the submounts 4a, 4b. , the distance from the light emitting point on the light emitting end surface of the semiconductor laser element to the bottom surface of the recess 10r can be increased by the thickness of the submounts 4a and 4b. Thereby, the light radiated from the LD element can be efficiently irradiated onto the light reflecting member 60 . Each submount 4a, 4b is provided with a wiring electrode, and each semiconductor laser element is fixed on each submount 4a, 4b by a bonding member such as AuSn.

Aluminum nitride or silicon carbide, for example, can be used as the submounts 4a, 4b.

Here, the reason why the semiconductor laser element 1 is mounted alone on the submount 4a and the semiconductor laser elements 2 and 3 are mounted on the submount 4b together with the protective element 8 is that GaAs crystals are GaN-based crystals. This is because it is a material with less crystal defects and has a relatively high electrostatic withstand voltage.
In the following description, a laser unit includes the submounts 4a and 4b and the semiconductor laser elements mounted on the submounts 4a and 4b.

(4) Preparation of Light Reflecting Member 6 As shown in FIG. 1, the light reflecting member 6 has, for example, a substantially triangular prism shape having three side surfaces, one of which is a reflecting surface. It is a member that reflects light and emits laser light in a predetermined direction. The light reflecting member 6 is provided on the bottom surface of the concave portion 10r so that the laser light of each semiconductor laser element is incident on the reflecting surface at a predetermined angle. By using this light reflecting member 6, the direction of light traveling parallel to the bottom surface of the recess 10r can be changed to the direction perpendicular to the bottom surface of the recess 10r. As a result, the direction of emission of laser light from each semiconductor laser element can be made parallel to the bottom surface of the recess 10r, and the light emitting device can be made thin.

As the light-reflecting member 6, it is possible to use a base material on which a reflective film is formed, or a base material itself formed of a highly reflective metal or the like without providing a reflective film. As the base material, quartz, glass such as BK7, and materials relatively heat-resistant such as Si can be used. A metal may be used as the base material. As the reflective film, a metal having a high reflectance, a dielectric multilayer film, or the like can be used. The reflective film may be formed only on the light reflecting surface. The light reflecting member 6 may be divided into a plurality of light reflecting members. For example, a plurality of light reflecting members may be used corresponding to the semiconductor laser elements 1, 2, and 3, respectively.

(5) Preparation of Light-Transmitting Member 20 The light-transmitting member 20 is a member having a light-transmitting property that allows laser light to pass therethrough. is hermetically sealed. The translucent member 20 is provided with a bonding metal film 20m on the outer peripheral portion of the lower surface, and the bonding metal film 20m is attached to the bonding metal film 10m provided around the recess 10r of the package 10, and the solder ball 15 is attached to the bonding metal film 10m. and fixed to the package 10 . As the translucent member 20, for example, glass provided with the bonding metal film 20m or sapphire provided with the bonding metal film 20m can be used. Among them, it is preferable to use sapphire provided with a bonding metal film 20m. For example, sapphire has relatively high strength and is hard to be damaged, so that the airtightness reliability in the recess 10r in which the semiconductor laser element is arranged can be improved. In addition, since sapphire has a higher thermal conductivity than glass, heat is easily conducted during the temporary bonding process and the final bonding process, which will be described later, and the solder balls are easily softened and melted.

In the method of manufacturing a semiconductor device according to the first embodiment, a light-emitting device is manufactured by incorporating the prepared laser unit, the light reflecting member, the translucent member 20, etc. into the prepared package 10 through the following steps.

1. Mounting Process In the mounting process, as shown in FIG. 1, the laser units 1u, 2u, 3u and the light reflecting member 6 are mounted on the bottom surfaces of the recesses 10r of the packages 10 of the collective substrate 100, respectively. Here, for example, each member is mounted as the following arrangement. The laser units 1u, 2u, 3u are arranged so that the laser beams emitted from the semiconductor laser elements 1, 2, 3 are parallel to each other and are emitted in parallel to the bottom surface of the recess 10r. Further, the light reflecting member 6 is arranged so that the laser light emitted from the semiconductor laser elements 1, 2 and 3 is reflected upward by the reflecting surface 6a. AuSn, Ag particle paste, Au particle paste, or the like can be used as the bonding member for mounting.

2. Wire Bonding Process In the wire bonding process, as shown in FIG. 2, the wiring electrodes of the laser units 1u, 2u, 3u and the wiring electrodes in the recess 10r are connected by wires 7. FIG.

3. Solder Ball Forming Step In the solder ball forming step, as shown in FIG. 3, a plurality of solder balls 15 made of, for example, AuSn are arranged at intervals on the bonding metal film 10m on the upper surface of the package 10 . Solder such as AuSn is used for the solder ball 15 . The solder ball 15 can be formed with a diameter in the range of 80 to 400 μm, for example. The diameter of the solder balls 15 and the spacing between the adjacent solder balls 15 are appropriately set so that an appropriate airway can be secured in the temporary fixing process described below and airtight sealing can be ensured in the main bonding process. The diameter of the solder ball 15 is preferably in the range of 100-200 μm. If the diameter of the solder ball is less than 100 μm, the volume of the solder ball is not sufficient to sufficiently fill the unevenness of the bonding surface when bonding a device such as a ceramic package whose bonding surface does not have good flatness. is difficult. Further, when the diameter of the solder ball is 200 μm or more, the volume of the solder ball is excessive, and the solder ball expands more than necessary during bonding. Also, the interval between adjacent solder balls 15 is preferably set in the range of 100 to 1000 μm. The above range is determined depending on the diameter of the solder ball. If the diameter of the solder ball is within the above range, the molten solder ball spreads just enough in the bonding step, and effective bonding can be obtained. The shape of the solder ball 15 is not limited to a spherical shape, and may be an elliptical sphere, a hemisphere, or an elliptical hemisphere. Here, the diameter of the solder ball 15 means the maximum diameter of the solder ball 15 . In addition, when the diameter of the solder ball cannot be formed within the above range, a plurality of solder balls 15 may be formed by overlapping at the same position. By doing so, the solder ball 15 can be formed with a desired volume. Therefore, in the temporary fixing step described later, an appropriate airway is ensured, and airtight sealing can be ensured in the main bonding step. At that time, the shape and/or diameter of the overlapping solder balls 15 may be different from that in the case of one solder ball.

In the solder ball forming process described above, an example has been described in which a plurality of solder balls 15 are formed at intervals on the surface of the package 10 around the recess 10r provided with the semiconductor laser element. Alternatively, for example, a plurality of solder balls may be formed at intervals on the bonding metal film 20m provided on the outer peripheral portion of the translucent member 20 by turning it upside down. In this case, in the temporary fixing step described later, the bonding metal film 10m provided on the surface of the package 10 is brought into contact with the upper surface of the softened solder ball 15 and temporarily fixed.

As described above, the plurality of solder balls 15 may be formed on the surface of the package 10 or may be formed on the surface of the translucent member 20. It is preferable to form it on the member having the higher thermal conductivity among the thermally conductive members 20 . By doing so, heat can be easily conducted to the solder balls 15 in the following temporary fixing process and bonding process. For example, when the package 10 is mainly made of AlN ceramics and the translucent member 20 is mainly made of sapphire, the solder balls 15 are formed on the surface of the package 10 .

4. Bonding Step In the bonding step, (1) the surface of the translucent member 20 (the surface of the bonding metal film 20m provided on the bottom surface) is formed so that an airway leading to the recess 10r is formed between the solder balls 15, (2) depressurizing the interior of the recess 10r through the airway formed between the solder balls 15, and after depressurizing, sealing gas. is injected, the translucent member 20 and the package 10 are heated and pressed together. In this bonding step, the solder balls 15 are melted to bond the translucent member 20 and the package 10 together.
Here, the heating and pressing does not limit the order of the timing of heating and the timing of pressing, but heating and then pressing in a heated state, pressing and then heating in a pressed state, Including all simultaneous heating and pressing.
The joining process will be described in more detail below.

(1) Temporary Fixing Step In the temporary fixing step, the translucent member 20 is aligned so that the bonding metal film 20 m formed on the outer periphery of the lower surface of the translucent member 20 faces the plurality of solder balls 15 . and temporarily fixed on the concave portion 10r. In the temporary fixing step, for example, the translucent member 20 is pressed onto the solder balls at a temperature lower than the melting point of the solder balls. This facilitates joining. It is preferable that the heating temperature of the package 10 is lower than the heating temperature of the translucent member 20 when joining in the temporary fixing step. By doing so, it is possible to reduce the deterioration of the electrodes provided on the package 10 and the laser units 1u, 2u, and 3 due to thermal damage, and to suppress the drive voltage rise of the laser units. Also, the temperature of the translucent member 20, which has a lower thermal conductivity than the package, can be raised in a short period of time. For example, when AnSn having a melting point of 285° C. is used as the solder balls 15, the heating temperature of the translucent member 20 is set in the range of 230° C. to 270° C., and the heating temperature of the package 10 is set in the range of 180° C. to 220° C. Set to range. Thermocompression bonding conditions such as heating temperature, pressure, and time at the time of thermocompression bonding are appropriately set in consideration of the shape and diameter of the solder balls 15 and the spacing between adjacent solder balls 15 .

In this temporary fixing step, for example, using a die bonder or the like, the solder balls 15 are heated to a temperature below the melting point through the light-transmitting member 20 and, if necessary, the light-transmitting member 20 and the package 10 to soften them. Let As a result, the translucent member 20 is brought into contact with the upper surfaces of the softened solder balls 15 and temporarily fixed so that an airway communicating with the recess 10 r is formed between the solder balls 15 . The temporary fixing process is performed so that adjacent solder balls do not come into contact with each other when the solder balls are softened. As a result, an airway leading to the recess 10r can be ensured. Note that the temporary fixing process can be performed in the air, and does not need to be performed in a vacuum chamber as in the following main bonding process. In the case of temporary fixing outside the vacuum chamber, bonding can be performed with high positional accuracy as compared with the case of temporary fixing or permanent bonding without temporary fixing in the vacuum chamber. Further, by temporarily fixing the package 10 outside the vacuum, it is possible to prevent the translucent member 20 and the package 10 from shifting when the package 10 is transported.

(2) Main Bonding Step In the main bonding step, first, the package 10 (collective substrate 100) to which the translucent member 20 is temporarily fixed is carried into a vacuum chamber. Next, by decompressing the inside of the vacuum chamber, the interior of the recess 10 r covered with the translucent member 20 is decompressed through the airway formed between the solder balls 15 . After decompressing the inside of the recess 10r, the sealing gas is injected into the recess 10r by introducing the sealing gas into the vacuum chamber. Then, the translucent member 20 and the package 10 are heated and pressed while the sealing gas is injected into the recess 10r.
For this heating and pressing, for example, a hot press equipped with an upper mold (first pressing body) and a lower mold (second pressing body) whose heating temperatures can be adjusted is placed in a decompressible vacuum chamber, Using this, for example, it is performed as follows.

First, as schematically shown in FIG. 5, a collective substrate 100 having translucent members 20 mounted on recesses 10r is placed between an upper mold 31 and a lower mold 32 in a vacuum chamber. Deploy.

Next, the upper mold 31 and the lower mold 32 are brought into contact with the collective substrate 100 from above and below to such an extent that the airways formed between the solder balls 15 are not blocked. In this state, the pressure in the vacuum chamber is reduced, and after the pressure is reduced, a sealing gas is introduced into the vacuum chamber. As a result, the sealing gas is injected into the recess 10r covered with the translucent member 20 through the airway formed between the solder balls 15. As shown in FIG. As the sealing gas, for example, a mixed gas containing dry air and helium gas can be used. When a mixed gas containing dry air and helium gas is used, the ratio of oxygen and nitrogen constituting the dry air to helium gas is, for example, 20% oxygen, 60% nitrogen, and 20% helium.

Next, while the sealing gas is injected, the translucent member 20 and the package 10 are heated and pressed by the upper mold 31 and the lower mold 32 .
At this time, the heating temperature by the upper mold 31 and the lower mold 32 is such that, for example, the solder balls 15 are heated to a temperature equal to or higher than the melting point. When heating, for example, it is preferable to lower the temperature of the lower mold 32 than the temperature of the upper mold 31 and lower the heating temperature of the package 10 than the heating temperature of the translucent member 20 . That is, the upper metal mold 31 (first pressing body) heated at a first temperature is brought into contact with the translucent member 20 and pressed, and the lower metal heated at a second temperature lower than the first temperature is placed on the package 10 side. It is preferable to bring the mold 32 (second pressing body) into contact and press, thereby melting the solder balls 15 and joining the translucent member 20 and the package 10 . By doing so, it is possible to reduce deterioration of the electrodes provided on the package 10 and the laser units 1u, 2u, and 3u due to thermal damage, and to suppress an increase in driving voltage of the laser units.
For example, by heating and pressing the package 10 so that the temperature is lower than the melting point of the bonding material used when mounting the semiconductor laser element in the concave portion 10r, the mounting position of the semiconductor laser element from a predetermined position is lowered. deviation can be suppressed.
Further, in the case where the semiconductor laser element is bonded on the submounts 4a and 4b by the first bonding member and the submounts 4a and 4b are mounted in the recess 10r by the second bonding member, for example, the package 10 is heated and pressed at a temperature lower than the melting point of the first joining member and the melting point of the second joining member. As a result, deviation of the mounting position from the predetermined position of the semiconductor laser element can be suppressed. In the main bonding step, for example, the temperature of the upper mold 31 (first pressing body) is set to 280° C. or higher and 400° C. or lower, and the temperature of the lower mold 32 (second pressing body) is set to 100° C. or higher and 200° C. or lower. Preferably. Moreover, it is preferable that the load at the time of pressing is in the range of 10 N or more and 100 N or less per 1 cm ² .

In the above bonding process, a buffer sheet having heat resistance and flexibility that can withstand the heating temperature is placed between the upper mold 31 (first pressing body) and the translucent member 20, and the translucent member 20 is attached. It is preferable to heat and press via a buffer sheet. In this way, the entire translucent member 20 can be uniformly pressed, and each can be reliably airtightly sealed. The hermetic sealing can be determined, for example, by the amount of dry air leaked. If the leak amount of dry air is 10 ⁻⁸ Pa·m ³ /s or less, it is considered that hermetic sealing is sufficiently achieved. In addition, by using the buffer sheet, the contact heat resistance between the upper mold 31 (first pressing body) and the translucent member 20 can be reduced, that is, the heat conduction can be improved, thereby improving the translucent member. 20 can be efficiently heated.
Here, for example, a carbon sheet can be used as the buffer sheet. A carbon sheet is suitable because it has high heat resistance and flexibility and compression recovery over a wide temperature range. Carbon sheets are also suitable in that they do not generate gas that contaminates the sealing gas, compared to other elastic members such as rubber.

Further, in the above joining process, instead of or in addition to the cushioning sheet arranged between the upper mold 31 (first pressing body) and the translucent member 20, the lower mold 32 (second A buffer sheet having heat resistance and flexibility that can withstand the heating temperature may be arranged between the pressing body) and the package 10 .
When a buffer sheet is arranged between the lower mold 32 (second pressing body) and the package 10, the contact state on the bottom side of the package 10 is improved, and heat can be efficiently dissipated. As a result, for example, when the heating temperature of the lower mold 32 is lower than the heating temperature of the upper mold 31, the heat on the upper mold 31 side can be efficiently released to the lower mold side. Temperature rise can be suppressed. A carbon sheet can be used as the cushioning sheet on the lower die 32 side, similarly to the cushioning sheet on the upper die 31 side.

5. Singulation Process As shown in FIG. 6, the assembled light emitting device is divided into individual elements using a breaking blade 40, for example. As described above, the collective substrate is preliminarily provided with cuts for singulation, so that it can be cut into pieces by pressing the breaking blade 40 against the cuts. In this singulation process, a breaking blade 40 is pressed from the package side. In this way, compared to the case where the blade 40 for breaking is pressed from the side of the translucent member 20, it is possible to suppress damage to the translucent member. FIG. 7 shows the individualized light emitting device.
As described above, a light-emitting device in which the semiconductor laser element provided in the recess 10r is airtightly sealed by the translucent member 20 can be manufactured.

According to the manufacturing method of the semiconductor device of Embodiment 1 configured as described above, since the temporary fixing process is provided before the main bonding process, the temporary fixing process can be performed outside the vacuum chamber. As a result, the translucent member and the package can be joined with high positional accuracy. If the translucent member and the package are positioned in the vacuum chamber without performing the temporary fixing step, the inside of the vacuum chamber is observed through an observation window provided in the vacuum chamber. Then, since the observation range is limited, it may be difficult to detect the exact position. Also, the translucent member can be easily arranged using a general-purpose die bonder or the like.

Further, in the manufacturing method of the semiconductor device of the first embodiment, in the main bonding step, the inside of the recess 10r covered with the translucent member 20 is passed through the airway formed between the solder balls 15 by decompressing the inside of the vacuum chamber. is decompressed, and the sealing gas is injected after the decompression. As a result, it becomes possible to remove the moisture adhering to the package 10 and the adhering gas components by utilizing this reduced pressure. Therefore, it is not necessary to remove adhering moisture or adhering gas components by heating at a temperature of 200° C. for a long time, for example, compared to the case where temporary fixing is not performed, and deterioration of the semiconductor laser element due to long-term heating is suppressed. can.

Further, according to the method of manufacturing the semiconductor device of Embodiment 1, it is possible to perform hermetic sealing all at once using the collective substrate 100. Therefore, the cost is lower than that of a light emitting device configured using a CAN package. can be manufactured to

In the first embodiment described above, the method for manufacturing a semiconductor device has been described by taking the case of manufacturing a light-emitting device as an example. However, the method for manufacturing a semiconductor device according to Embodiment 1 is not limited to manufacturing a light-emitting device, and can also be applied to other semiconductor devices that require hermetic sealing. Even when the method is applied to other semiconductor devices, the translucent member and the package can be joined with high positional accuracy in the same manner as in the semiconductor device manufacturing method of the first embodiment. Moreover, it becomes possible to manufacture a semiconductor device at low cost.

Note that the semiconductor device described in the above first embodiment may include other members such as a wiring board and a collimating lens. For example, the light emitting device 50 can emit collimated light from each semiconductor laser element by providing a collimating lens on the translucent member 20 as described below.

For example, a light-emitting device having a collimator lens can be manufactured by using the light-emitting device 50 manufactured by the manufacturing method of the first embodiment and further through the following steps.

6. Wiring Substrate Mounting Step Here, as shown in FIG. 8, the package 10 of the light emitting device 50 manufactured by the manufacturing method of the first embodiment is mounted on the wiring substrate 110 . As shown in FIG. 8, the wiring substrate 110 is made of, for example, ceramics, and includes a substrate 111 formed with a metal film 112 that functions as an alignment mark when the package 10 is mounted on the wiring substrate 110, a light emitting device 50, and an electrical wiring board 111. and a metal film 114 for fixing the heat dissipation surface of the package 10 and the substrate 111 . The substrate 111 is preferably made of the same material as the package 10. For example, when the package 10 is made of ceramics, the substrate 111 is made of the same ceramic material.

7. Step of Attaching Collimator Lens Next, as shown in FIG. 9, the collimator lens 70 is attached on the translucent member 20 . An adhesive 90 is applied to the four corners of the upper surface of the translucent member 20, and the collimating lens 70 is aligned and fixed. The collimating lens 70 can be made of glass such as borosilicate glass. The collimator lens 70 includes a first lens portion 71 for emitting the laser light emitted by the semiconductor laser element 1 in a predetermined direction, and a second lens portion 72 for emitting the laser light emitted by the semiconductor laser element 2 in a predetermined direction. , and a third lens portion 73 for emitting laser light emitted from the semiconductor laser element 3 in a predetermined direction. Also, the non-lens portion 74 is provided so as to surround the first lens portion 71 , the second lens portion 72 and the third lens portion 73 .
A light-emitting device having a collimator lens manufactured as follows can emit parallel light from each semiconductor laser element.

Also, the method of manufacturing a semiconductor device is not limited to the above. When hermetic sealing is performed without vacuuming, for example, the following method can be used.

<Embodiment 2>
A method of manufacturing a semiconductor device according to a second embodiment is a method of manufacturing a semiconductor device including sealing a semiconductor laser element provided in a recess of a package by covering the recess with a translucent member. A ball forming step and a joining step are included. The solder ball forming step is a step of forming a plurality of spaced apart solder balls on the surface of the package around the recess in which the semiconductor laser element is provided, or on the surface of the translucent member facing the surface. be. In the bonding step, the package and the light-transmitting member are separated from each other into a container having an air supply port for supplying sealing gas and an exhaust port for discharging sealing gas, or such that an airway is formed between solder balls. while supplying the sealing gas to the container in an integrated state, heating the package or the translucent member in which the solder balls are formed, and pressing at least one of the package and the translucent member By doing so, the solder balls are melted to join the surface of the translucent member and the surface of the package.

According to the semiconductor device manufacturing method of the second embodiment, since a vacuum chamber is not used, it is possible to provide a semiconductor device capable of bonding the translucent member and the package with high positional accuracy.

The method for manufacturing the semiconductor device of Embodiment 2 will be described in detail below. However, items that are substantially the same as those of the first embodiment may be omitted as appropriate.

(1) Preparation of Package The package 10 will be described with reference to FIG.
The preparation of the package is substantially the same as that described in Embodiment 1 except for the following.
Here, the package 10 is prepared. The package 10 may be pre-divided into individual pieces, or may be an aggregate substrate 100 on which a plurality of packages 10 are provided in an aggregated state.
The package 10 has an outer peripheral portion 10n for disposing the translucent member 20, a surface to which the translucent member 20 is bonded, and a recess 10r in which the semiconductor laser unit is provided. The surface of the outer peripheral portion 10n is higher than the surface to which the translucent member 20 is joined. The surface to which the translucent member 20 is bonded has a shape with corners. Of the corners of the surface of the package surrounding the recess 10r and to which the translucent member 20 is bonded, the radius of curvature of the corner on the recess 10r side is larger than the radius of curvature of the corner on the outer peripheral portion 10n side.

If the material of the package 10 and the material of the translucent member 20 are different, the linear expansion coefficients of both may not match. In such a case, the bonding material that bonds the two may receive thermal stress due to the difference in linear expansion coefficient between the package 10 and the translucent member 20 and may be damaged.
In Embodiment 2, as shown in FIG. 10, of the corners of the package surface that surrounds the recess 10r and to which the translucent member 20 is bonded, the radius of curvature of the corner on the side of the recess 10r is the same as that of the outer peripheral portion 10n. preferably larger than the radius of curvature of the side corners. By making the curvature of the concave portion as described above, it is possible to reduce the possibility that the bonding material that bonds the package 10 and the translucent member 20 is damaged due to the influence of thermal stress. When it is desired to reduce the size of the entire package, it is preferable to make the shape of the corners on the outer peripheral side depend on the shape of the translucent member 20 . In the case of a material that complicates the process of imparting curvature to the corners of the translucent member 20, it is difficult to sufficiently increase the radius of curvature on the outer peripheral side. However, the concentration of thermal stress can be reduced by setting the radius of curvature of the corners on the concave side as described above. Sapphire, for example, can be used as such a translucent member 20 .
Further, by adopting the package shape as described above, it is possible to arrange more solder balls in the corners than in the regions other than the corners. By arranging a large number of solder balls 15, the adhesion between the package 10 and the translucent member 20 is enhanced, and the sealing gas is less likely to leak.

(2) Preparation of Semiconductor Laser Device As the semiconductor laser device to be prepared, the same material and emission peak wavelength as in the first embodiment can be used for the semiconductor laser device. It is not limited to the three-color semiconductor laser elements 1, 2, and 3 of RGB. Either one color of RGB or two colors may be used. Moreover, any one color may be provided in plural numbers. In the second embodiment, a mode in which a semiconductor laser element emitting blue light is used will be described.

(3) Mounting of the semiconductor laser element on the submount and (4) Preparation of the light reflecting member The number and emission color of the mounted semiconductor laser elements can be appropriately changed to form the laser unit. It is substantially the same as the matter explained.

(5) Preparation of Translucent Member The translucent member 20 will be described with reference to FIG. 11A.
The preparation of the translucent member is substantially the same as the items described in the first embodiment except for the items described below.
When the blue semiconductor laser element 3 is used, as shown in FIG. 11A, the translucent member 20 may further include a wavelength conversion member 21 in order to make the light emitted from the semiconductor device white. The wavelength conversion member 21 is excited by the laser light emitted from the semiconductor laser element 3 and emits light having a wavelength different from that of the laser light. For example, the wavelength conversion member can be formed of a single-crystal or polycrystalline phosphor, a composite of phosphor and reflector, or a sintered body obtained by molding and firing phosphor powder and reflector. As the phosphor 21p, a so-called YAG phosphor having cerium as an activator and yttrium-aluminum-garnet (hereinafter referred to as YAG) as a base can be used. As the reflecting material 21r, aluminum oxide, aluminum nitride, YAG containing no activator, yttrium oxide, or the like can be used.

In the method of manufacturing a semiconductor device according to the second embodiment, the laser unit 3u, the light reflecting member 6, the translucent member 20, etc. prepared are incorporated into the prepared package 10 through the following steps to manufacture the light emitting device. .

1. mounting process;2. wire bonding process; and3. Solder Ball Forming Process The mounting process, wire bonding process and solder ball forming process are substantially the same as those described in the first embodiment. The solder balls 15 may be provided either on the surface around the recess of the package 10 or on the surface of the translucent member 20 facing the surface. A case will be described.

4. Bonding Step In the bonding step in Embodiment 2, the surface of the translucent member and the surface of the package are bonded with a melted solder ball. At this time, the package and the light-transmitting member are separated from each other or integrated into a container having an air supply port for supplying the sealing gas and an exhaust port for discharging the sealing gas, or the package and the light-transmitting member are integrated so that an airway is formed between the solder balls. The package and the light-transmitting member are heated to press at least one of the package and the light-transmitting member while supplying the sealing gas to the container while the solder balls are formed.
Here, the phrase "accommodate the package and the light-transmissive member separately" includes both the case of accommodating the package and the translucent member at the same time and the case of accommodating the package and the translucent member at different timings. Moreover, when they are accommodated at different timings, either the package or the translucent member may be accommodated first.
Moreover, the order of heating the package in which the solder balls are formed or the translucent member and pressing at least one of the package and the translucent member may come first.

The bonding process will be described below with reference to FIGS. 12A and 12B.
First, a container having at least an air supply port 123in and an exhaust port 123out is placed on a stage 122 having a heater. The container 120 and the stage 122 may be integrally formed, in which case these members can be collectively regarded as one container.
The sealing gas is supplied through a gas line 123 and introduced into the container 120 through an air supply port 123in. The container 120 has an exhaust port 123out through which the sealing gas is exhausted to the outside of the container. At that time, the moisture-containing gas originally filled in the container is also exhausted. As a result, the package can be hermetically sealed with the translucent member while the container 120 is filled with dry gas, ie, the recess 10r of the package 10 is filled with dry gas. As a result, the dew point of the semiconductor device is lowered as compared with the case where the semiconductor device is sealed with gas containing moisture.
The sealing gas is preferably continuously supplied from before the package 10 is introduced into the container 120 until the bonding process is completed. As a result, the atmosphere in the container 120 can be more reliably replaced with the sealing gas.
The flow rate of the sealing gas is preferably 5 liters per minute or more. The gas in the container 120 can be sufficiently replaced, and the dew point of the semiconductor device is lowered. Also, the upper limit of the temperature of the sealing gas may be less than the melting point of the solder ball 15 . For example, when the material of the solder balls 15 is AuSn, the temperature of the sealing gas should be 280° C. or less.
As the sealing gas, a mixed gas containing dry air and helium gas can be used as in the first embodiment.

Moreover, it is preferable that the temperature of the stage 122 is lower than the melting point of the solder balls 15 and is warmed to near the melting point of the solder balls 15 . Warm until the temperature difference from the melting point is, for example, 30°C or less. It is preferably 20° C. or lower, more preferably 10° C. or lower. By preheating the stage 122, when the package 10 having the solder balls 15 formed thereon is placed on the stage 122, the temperature of the package 10 is increased in a short time compared to the case where the package 10 is placed and then heated. can reach the melting point of the solder ball 15 or higher. As a result, lead time can be shortened.

Next, the package 10 in which the solder balls 15 are formed and the translucent member 20 are accommodated in the container 120 respectively. As shown in FIG. 12B , the surface of the package 10 and the surface of the translucent member 20 are joined via the solder balls 15 by pressing the translucent member 20 using the pressing body 124 . However, the package 10 and the translucent member 20 may be accommodated before or after the sealing gas is supplied into the container 120 . Alternatively, the translucent member 20 attached to the pressing member 124 may be introduced into the container 120 and joined to the package 10 . The load applied by the pressing body 124 is preferably 1N or more and 200N or less. More preferably, it is 1N or more and 100N or less. Since the inside of the container is filled with the sealing gas, there is a possibility that the solder balls 15 will not spread sufficiently just by placing the translucent member 20 on the package 10 . By applying a load of the above degree, it is possible to widen the range to a sufficient extent for bonding.

In the bonding process described above, an example has been described in which a plurality of solder balls 15 are formed at intervals on the surface of the package surrounding the recess 10r and to which the translucent member 20 is bonded. Alternatively, for example, a plurality of solder balls may be formed at intervals on the bonding metal film 20m provided on the outer peripheral portion of the translucent member 20 . In this case, it is conceivable to place the translucent member 20 on the stage 122 and apply pressure to the package 10 using the pressing body 124 to join.

5. Singulation Process The singulation process is a process performed when the aggregate substrate 100 is prepared in the package preparation process. For example, it is performed as in the first embodiment. If it has already been singulated before the joining step, the singulation step need not be performed here.

According to the semiconductor device manufacturing method of the second embodiment configured as described above, since a vacuum chamber is not used, the translucent member and the package can be joined with high positional accuracy.

Further, according to the method for manufacturing a semiconductor device of Embodiment 2, by substituting the atmosphere inside the container with the sealing gas, the amount of moisture contained in the semiconductor device is reduced even in a state in which vacuuming is not performed. The light-emitting device and the translucent member can be hermetically sealed.

FIG. 11B is a top view of a light-emitting device 50 in which the package 10 and the translucent member 20 having the wavelength conversion member 21 are joined together. A laser beam oscillated from the semiconductor laser is raised by the light reflecting member 6, passes through the phosphor 21p of the wavelength converting member 21, becomes white light, and is emitted to the outside of the light emitting device.

Reference Signs List 1, 2, 3 semiconductor laser element 1u, 2u, 3u laser unit 4a, 4b submount 6 light reflecting member 6a reflecting surface 7 wire 8 protection element 10 package 10m, 20m bonding metal film 10n outer peripheral portion 10r concave portion 15 solder ball 15a Bonding material 20 Translucent member 21 Wavelength conversion member 21r Reflective material 21p Phosphor 31 Upper mold 32 Lower mold 50 Light emitting device 70 Collimating lens 71 First lens part 72 Second lens part 73 Third lens part 74 Non-lens part 90 Adhesive 100 Assembled Substrate 110 Wiring Substrate 111 Substrate 112 Metal Film 113 Wiring Electrode 114 Metal Film 120 Container 122 Stage 123 Gas Line 123 inch Air Supply Port 123 Out Exhaust Port 124 Pressing Body

Claims (11)

A method of manufacturing a semiconductor device, comprising sealing a semiconductor laser element provided in a recess of a package by covering the recess with a translucent member,
a solder ball forming step of forming a plurality of spaced apart solder balls on the surface of the package around the recess in which the semiconductor laser element is provided, or on the surface of the translucent member facing the surface;
a temporarily fixing step of temporarily fixing the surface of the translucent member or the surface of the package by contacting the upper surfaces of the softened solder balls so that an airway leading to the recess is formed between the solder balls; ,
The interior of the concave portion is decompressed through the airway, and in a state in which sealing gas is injected after the decompression, the translucent member and the package are heated and pressed to melt the solder balls and melt the solder balls. a bonding step of bonding the translucent member and the package ,
A method of manufacturing a semiconductor device, wherein in the bonding step, the heating temperature of the package is lower than the heating temperature of the translucent member . 2. The method of manufacturing a semiconductor device according to claim 1 , wherein said translucent member is heated to a temperature equal to or higher than the melting point of said solder ball in said bonding step. In the bonding step, a first pressing body heated at a first temperature is brought into contact with the translucent member, and a second pressing body heated at a second temperature is brought into contact with the package, whereby the first pressing body and the second pressing body are brought into contact with each other. 3. The manufacturing of the semiconductor device according to claim 2 , wherein the solder ball is melted by pressing 2 pressing bodies to join the translucent member and the package, and the second temperature is lower than the first temperature. Method. 4. In said joining step, an elastically deformable buffer sheet is arranged between said first pressing body and said translucent member , and said translucent member is heated and pressed through said buffer sheet. A method of manufacturing the semiconductor device according to 1. 5. The semiconductor according to claim 3 , wherein in said joining step, an elastically deformable buffer sheet is arranged between said second pressing body and said package, and said package is heated and pressed via said buffer sheet. Method of manufacturing the device. 6. The method of manufacturing a semiconductor device according to claim 1 , wherein said package is a ceramic package. 7. The method of manufacturing a semiconductor device according to claim 1 , wherein said solder balls are AuSn balls. 8. The method of manufacturing a semiconductor device according to claim 1 , wherein in said temporary fixing step, said solder balls are softened at a temperature lower than the melting point of said solder balls. 3. The semiconductor laser elements include a first semiconductor laser element that emits red laser light, a second semiconductor laser element that emits green laser light, and a third semiconductor laser element that emits blue laser light. 9. The method for manufacturing a semiconductor device according to any one of 1 to 8 . an element mounting step of mounting the semiconductor laser element in the recess by a first bonding member before the solder ball forming step;
10. The method of manufacturing a semiconductor device according to claim 1 , wherein in said bonding step, said package is heated and pressed at a temperature lower than the melting point of said first bonding member. The element mounting step comprises: a first mounting step of bonding the semiconductor laser element onto a submount using the first bonding member; and mounting the submount to which the semiconductor laser element is bonded in the recess using a second bonding member. including a second mounting step,
11. The method of manufacturing a semiconductor device according to claim 10 , wherein in said bonding step, said package is heated and pressed at a melting point of said first bonding member and a temperature lower than the melting point of said first bonding member.

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